1. Field of the Invention
The present invention relates to a plastic molding including a core which is provided on an outer surface thereof with a foam with an outer skin, and a method for producing the same.
2. Description of the Related Art
For instance, a conventional instrument panel for an automobile is usually made of a core 81 (base or substrate) which is provided, on a part or entirety (not shown) of the outer surface thereof, with a pad comprising a foam 83 with an outer skin, depending on a design, as shown in FIG. 18. FIG. 19 shows an enlarged sectional view taken along the line A--A in FIG. 18.
In an instrument panel made of a core and a foam with an outer skin, provided on a part of the outer surface of the core, a foam assembly 83 comprising a mounting base 84, a foam 86 and an outer skin member 87 is prepared in advance and is mounted to a core 81 at a predetermined position. To mount the foam assembly 83 to the core 81, mounting pins 85 provided on the base 84 of the foam assembly 83 are inserted and bent in mounting holes 82 formed in the core 81. Clips or screws, etc., can be used in place of the mounting pins 82.
However, since the foam assembly 83 is provided with the base 84 which is usually made of a steel plate, the instrument panel is heavy and expensive.
Moreover, since the foam assembly 83 is mounted to the core 81 in a subsequent stage, a gap or clearance tends to occur at a connecting portion 88 between the foam assembly 83 and the core 81, thus leading to a poor or bad appearance of the plastic molding (product). In particular, in an instrument panel made of a core whose outer surface is partly covered by the foam assembly, since the connecting portion 88 between the core 81 and the foam assembly 83 appears on the outer surface of the plastic molding, the gap or clearance is unacceptable from the aesthetic view point. Furthermore, an additional troublesome process to mount the foam assembly to the core is necessary.
In an instrument panel made of a core whose outer surface is entirely covered by the foam assembly, a skin member which is provided on the peripheral edge thereof with a skirt to prevent the surface of the skin from being stained is used. Namely, the skin member is disposed on a die surface of a lower die of a die assembly which is comprised of the lower die and an upper die, so that the skirt is located on a periphery of a cavity, i.e., a parting of the die assembly defined by the lower and upper dies. The core is disposed on the die surface of the upper die. When the upper and lower dies are closed, the skirt is held between the upper and lower dies. In the closed position, a foaming material is introduced and foamed in the cavity. The skirt is finally cut and removed to produce a plastic molding (product).
However, in the producing method mentioned above, the foaming material tends to flow or leak from the periphery of the cavity during foaming, thus resulting in an occurrence of a flash. Moreover, it is necessary to cut and remove the skirt of the skin member, which is stained with flash, and, troublesome. In addition to the foregoing, the foaming material sticking to the outer surface of the cut skirt makes it difficult to reuse the cut skirt, resulting in a waste of the material.